1. Field of the Invention
The present invention relates to an ink-jet printing cloth, an ink-jet printing process and a production process of a print.
2. Related Background Art
Besides screen printing and roller printing, ink-jet printing has heretofore been known as a process of printing on cloth formed of cotton, silk, polyester or the like. This ink-jet printing is conducted by means of an ink-jet printing apparatus obtained by improving an image-forming apparatus of an ink-jet system for forming images on recording media such as plastics and recording paper so as to be fitted for textile printing and the kind of cloth to be used.
The ink-jet system is a non-impact printing system, which ejects an ink or the like to directly apply the ink to cloth or the like and produces little noise. A textile printing apparatus equipped with an ink-jet system printing head permits high-density printing operation at high speed. The textile printing processes using a plate such as a screen or a design roller are unfit for multi-kind small-quantity production, whereas the ink-jet textile printing process is a system making no use of any plate, and permits multi-kind small-quantity production in a short period of time because data for printing can be formed with ease by a host system or the like.
The textile printing apparatus of the ink-jet system is generally equipped with a printing means (printing head) mounted on a carriage, a feeding means for feeding a cloth and control means for controlling these means. The printing head by which ink droplets are ejected through a plurality of ejection orifices is serially scanned in a direction (a main scanning direction) perpendicular to the feeding direction (a secondary scanning direction) of the cloth. On the other hand, the cloth is intermittently fed by a predetermined length at the time printing is stopped. According to this printing process, inks are ejected on the cloth according to printing signals to conduct printing. Therefore, the ink-jet printing process attracts attention as a printing method which is low in running cost and silent. When a printing head in which a plurality of ink-ejecting nozzles has been aligned in the secondary scanning direction is used, printing of a width corresponding to the number of the nozzles can be performed every time the printing head is scanned once on the cloth.
In the case of color textile printing, a color image is formed by overlapping ink droplets of plural colors ejected from respective printing heads. In general, color printing requires three or four printing heads and ink tanks corresponding to 3 primary colors of yellow (Y), magenta (M) and cyan (C) or 4 colors including black (B) in addition to these primary colors.
Since such devices are used, the techniques required of ink-jet printing are greatly different from those of screen and roller printing. This is caused by such differences in system as: the optimum value of viscosity of inks used in the ink-jet printing is greatly different from that of textile printing inks used in screen printing or the like and is low, ink-jet printing requires attention to reliability such as clogging of the head, the so-called additive color process, in which a few inks of different colors are shot on the same position so as to overlap each other, is conducted, and dots of inks are very small.
Various investigations have thus been attempted as to methods of such ink-jet printing. For example, Japanese Patent Publication No. 63-31594 discloses a method in which textile printing is conducted on a cloth containing a water-soluble polymer, a water-soluble salt and water-insoluble inorganic fine particles, and Japanese Patent Publication No. 63-31593 discloses a textile printing method in which inks each having a viscosity of 200 cP or lower and a surface tension of 30 to 70 dyn/cm are used, and a cloth having a water repellency of 50 points or more as measured in accordance with JIS L 1079 is employed.
Since the prior art printing methods described above are based on thinking that the penetration of inks into the interior of fiber is prevented to prevent the diffusion of dyes, thereby improving coloring, the improvement in coloring is recognized to some extent. However, they involve problems such as (1) it takes a long time to dry the inks, (2) no strike-through occurs because the inks do not spread, and (3) an area factor becomes small because the inks do not spread, and so coloring ability is limited.
On the other hand, for example, Japanese Patent Application Laid-Open No. 4-59282 discloses an ink-jet printing cloth obtained by incorporating 0.1 to 3% by weight of a surfactant into a cloth formed of a hydrophilic fiber material. According to the cloth subjected to such a treatment, inks are absorbed in the interior of the fiber by diffusion, and so the tendency to strike-through is enhanced. However, such a cloth is unfavorable with respect to improvement in coloring ability because dyes penetrate into the interior of the fiber.
As described above, the prior art techniques have been able to satisfy individual performance characteristics required of the ink-jet printing process for obtaining excellent prints to some extent, but have been unable to satisfy all the performance characteristics at the same time.